MatrixMultiplication.java

import java.util.Scanner;
 
public class MatrixMultiplication
{
   public static void main(String args[])
   {
      int m, n, p, q, sum = 0, c, d, k;
 
      Scanner in = new Scanner(System.in);
      System.out.println("Enter the number of rows and columns of first matrix:");
      m = in.nextInt();
      n = in.nextInt();
 
      int first[][] = new int[m][n];
 
      System.out.println("Enter elements of first matrix:");
 
      for (c = 0; c < m; c++){
         for (d = 0; d < n; d++){
            first[c][d] = in.nextInt();
        }
        }
      System.out.println("Enter the number of rows and columns of second matrix:");
      p = in.nextInt();
      q = in.nextInt();
 
      if (n != p)
      {
         System.out.println("The matrices can't be multiplied with each other.");
        }
        else
      {
         int second[][] = new int[p][q];
         int multiply[][] = new int[m][q];
 
         System.out.println("Enter elements of second matrix:");
 
         for (c = 0; c < p; c++){
            for (d = 0; d < q; d++){
               second[c][d] = in.nextInt();
            }
        }
         for (c = 0; c < m; c++)
         {
            for (d = 0; d < q; d++)
            {  
               for (k = 0; k < p; k++)
               {
                  sum = sum + first[c][k]*second[k][d];
               }
 
               multiply[c][d] = sum;
               sum = 0;
            }
         }
 
         System.out.println("Product of the matrices:");
 
         for (c = 0; c < m; c++)
         {
            for (d = 0; d < q; d++){
               System.out.print(multiply[c][d]+"\t");
            }
            System.out.print("\n");
         }
      }
   }
}